The reasons why cats push people with their heads:

1. Declaration of sovereignty: Cats are olfactory animals. Their sense of smell is very developed and their communication methods are also very special. Therefore, it will use rubbing or arching methods to leave its own scent on objects or people, which is used to tell others that this is its territory or that this is a person it is familiar with, in order to declare its sovereignty. If cat owners observe carefully, they will find that cats not only like to nudge people with their heads, but also like to rub their heads against sofas, table corners and other places at home.

2. Marking territory: Cats have a strong sense of territory and will mark their territory in various ways, including arching and rubbing. In this way, it leaves its own scent on its own territory, and it also serves to remind its fellow species not to infringe on its territory.

3. Express love to the owner: If the cat likes you very much, it will like to nudge you with its head. The cat is expressing its love for you in this way.

The physical behaviors of cats expressing emotions include:

1. Trust: When a cat trusts its owner, it will roll in front of the owner, stretch its limbs, or be beside the owner. Rubbing around, acting coquettishly towards the master.

2. Angry: When a cat is angry, it will lower its body, curl up its tail, press its ears back, open its mouth, expose its canine teeth, and make sounds, making an offensive posture.

3. Irritability: When a cat feels irritable, it will tap the ground vigorously with its tail to express its inner unhappiness.